1. Field of the Invention
The present application relates generally to fractionation tray hardware and more particularly, but not by way of limitation, to hardware utilized for securing fractionation trays within a chemical-process column.
2. History of the Related Art
Chemical-process columns are utilized to separate select components from a multicomponent stream. Successful separations in the chemical-process column are dependent upon intimate contact between heavier fluids and lighter fluids. Several types of contact mechanisms enhance contact between a fluid in a vapor phase and a fluid in a liquid phase. Contact devices such as, for example, trays are characterized by relatively high pressure drop and relatively high fluid hold-up. Other types of contact apparatus include high-efficiency packing. High-efficiency packing is energy-efficient because it has low pressure drop and low fluid hold-up.
Typically, chemical-process columns utilize either trays, packing, or combinations thereof. Tray designs such as, for example, sieve trays and valve tray are effective and often applied in chemical-process columns. A sieve tray is constructed with a large number of apertures formed in a bottom surface. The apertures permit an ascending lighter fluid to interact with a heavier fluid that is flowing across the sieve tray from a downcomer. Regions of the sieve tray surface are generally referred to as “active” or “inactive”. Typically, active tray regions allow the ascending lighter fluid to pass therethrough for interaction and mass transfer with the heavier fluid. Conversely, inactive tray regions do not permit such interaction. It is generally desirable to have as much of a tray surface as possible be “active”. Thus, it is desirable to secure the tray to an interior of the chemical-process column in a manner that minimizes inactive tray regions.
Trays are typically secured within chemical-process columns by clamps that engage a support affixed to an interior of the chemical-process column. Typically, the clamps are tightened by way of bolts arranged generally perpendicular to the tray. This method, while effective, is not without problems. First, in most cases, securement of a tray to the support requires a first individual positioned above the tray and a second individual positioned below the tray. Moreover, in cases where the support is thick, the clamps may deflect. As will be described in more detail below, such deflection induces a lateral force in the bolts which, over long periods of use, may cause the clamps to disengage from the support.